Offset frame construction



Oct. 1, 1963 r A. e. SCHIILBERG OFFSET FRAME CQNSTRUCTION Filed April; 5, 1961 INVENTOR.

mm ET e k K Gm U R J! 3 mm 1! "E w G. r D '4 c s 4 N6 R Y ANB E Attorneys United States Patent 3,105,701 OFFSET FRAME CONSTRUCTION Arnold G. Schilberg, deceased, late of Milwaukee, Wis., by Irene G. Schilberg, administratrix, Milwaukee, Wis., assignor to A. 0. Smith Corporation, Milwaukee, Wis, a corporation of New York Filed Apr. 5, 1961, Ser. No. 101,622

1 Claim. (Cl. 280-406) The present invention relates generally to offset frames and particularly to frames of this type having a continuous full length side rail component.

In the offset or wide-hipped frame as it is sometimes referred to, there are no full length side rails as such but rather a pair of separate and distinct fore, aft and center side rails. The fore and aft side rails lie within the front and rear wheels and are connected rigidly together by suitable cross bracing. The center side rails are mounted in laterally outwardly offset relation with the corresponding fore and aft side rails and are secured thereto by torque boxes and/ or additional cross braces mounted between the ends of each of the center side rails and the adjacent ends of the fore and aft side rails.

This type of frame is particularly well suited for use with vehicles having a low silhouette as it permits the body structure to be dropped more fully within the center of the frame and to the level of minimum ground clearance. As a consequence, there is more low level floor space in the vehicle and, in turn, more space in the vehicle for passengers.

From a production standpoint, the offset frame presented a number of unique problems. On the one hand, the number of frame components was increased appreciably over past designs, thus requiring a corresponding increase in the number of blanking, piercing, drawing, and upsetting operations and an increased number of assembly operations. Further, as the frame components have been considerably shorter in length than theretofore, previously used frame forming equipment had to be substantially revamped to handle the smaller pieces.

Apart from this, moreover, the offset frame was not considered to be as structurally efficient as it might be, due to the lack of continuity in the side rails and the abrupt offset provided between the various sections of the frame.

In the present invention, an offset or wide-hipped frame is provided in which the above problems are to a large extent minimized or overcome altogether by a structure in which one of the components of the side rail comprises an outer main channel member extending continuously the length of the frame. The channel member is curved gradually inwardly in the horizontal plane at predetermined fore and aft areas to provide the desired offset and the ends thereof are curved upwardly to provide the necessary side rail upset or kick-up to accommodate the front and rear wheel assemblies in the chassis structure.

The intermediate portion of the main channel member is boxed-in by an inner channel member which is extended to engage the web portion of the outer member in the horizontally curved area of the latter so as to add structural reinforcement thereto. The fore and aft portions of the outer member are similarly boxed-in by a pair of additional inner channel members. The ends of each of the fore and aft channel members are suitably curved with respect to both the horizontal and vertical to conform to the contour of the main channel member in the area of offset and kick-up and is joined to the corresponding 3,105,701 Patented Get. 1, 1953 of the invention represents a less costlyand simpler design and one which is more suited for fabrication on an assembly line basis with existing frame forming equipment.

The drawing furnished herewith illustrates the best mode presently contemplated of carrying out the invention.

In the drawing: I

FIG. I rep-resents a diagrammatic plan view of an offset or wide-hipped frame embodying the present invention;

FIG. 2 is a fragmentary view of FIG. 1 showing the construction of the side rail on an enlarged scale;

FIG. 3 is a side elevation of the structure of FIG. 2 taken on the lines 3-3 of FIG. 2; and I FIG. 4 is a section through the side rail along the lines 4-4 of FIG. 2.

The offset frame 1 of the invention includes a pair of laterally spaced, generally tubular side rails 2 extending lengthwise of the frame and having intermediate portions which are offset laterally outwardly relatively of the ends of the rails and substantially perpendicularly thereto to provide the relatively narrow fore and aft frame sections 3 and '4 respectively, and a relatively wide center or intermediate section 5. In this type of frame, the rails 2 in center section 5 are normally disposed at minimum ground clearance level. Accordingly rails 2 are kicked-up forwardly and rearwardly for wheel mounting purposes. Rails 2 are connected by a front cross brace assembly 6 located in frame section 3 and by a shock bar 7 and cross bar 8 located in frame section 4. Additional cross bracing for side rails 2 is provided in the form of a pair of hip cross bars 9 located one each in frame sections 3 and 5 immediately adjacent frame section 4.

In order to provide side rail continuity over the length of the frame and to also provide a more economical frame design, each of the side rails 2 is comprised in part of an outer channel member 10 formed as a full length member extending continuously the length of the frame. Members 10 are both kicked-up forwardly and rearwardly and curved inwardly in the horizontal plane adjacent and between each of the areas which are kicked-up, as shown.

Mounted to channel members 10 are a series of secondary channel members 11, 12 and 13 which are assembled to members 10 in a manner to be explained to provide a completely enclosed boxed rail construction.

The first of these members, member 11, is mounted to the generally straight, intermediate or center portion of each of main channel members 10 with the latter part- 1y overlapping member 11 as shown. To endow. the hip forming portions of members 10 with increased rigidity, the ends of member 11 are extended to meet the vertical, laterally curved wall of channel members 10 and are connected thereto by a Weld laid along contiguous portions of the members to thereby provide a bulkhead effect in the assembled rails 2.

The secondary members 112 and 13 enclose and are lapped by the fore and aft portions of members it respectively as in the case of member 11 and intermediate portion of member. 10, and the ends of members 12 and 13 adjacent center frame section 5 are bent laterally outwardly and upwardly to conform to the contour of the corresponding forward and rearward curved areas of channel members 10. The ends of members 12 and 13 thus bent abut the corresponding end of members (11 and are welded thereto and to main channel member 10, as shown.

By employing a full length side rail component in a frame of this type, the side rails are better able to resist externally applied loads on the frame and are more structurally eflicient than conventional type side rails which consisted of separate fore, aft and center side rails. The frame of the invention represents a considerable saving in frame and frame production costs as torque :boxes as such are not needed and fewer component pieces are required in the makeup of the frame.

Additionally, in the invention, side rails are bent gradually outwardly to provide the frame hips. As opposed to the right-angle hip construction formerly employed in offset frames, the design of the invention decreases to some extent the magnitude of twisting forces within the frame arising out of the crank action of the hips;

Various modes of carrying out the invention are contemplated as being within the scope of the following claim particularly pointing out and distinctly claiming the subject matter which is regarded as the invention.

What is claimed is: 1 A side rail for an olfset frame, comprising an inwardly facing main channel member forming the outer portion of the side rail and extending continuously the full length of the frame, said main channel member having substantially perpendicularly inwardly bent and upwardly curved forward and rearward portion-s, a first channel member secured in facing relation to said main a channel between said forward and rear-ward laterally bent and curved portions, said first channel member extending to and abutting against the outer portion of said main channel member in the laterally bent portions there-1 of and with the abutting portions of said main channel,

member and the first channel member secured rigidly together to provide a bulkheading efiect'in the side rail, and second channel members secured to the ends of said main channel member in facing relation thereto and extending to the ends of said first channel member and secured thereto.

References Cited in the file of this patent UNITED STATES PATENTS 2,157,353 Sherman May 9, 1939 2,194,356 Eklund Man-19, 1940 2,485,500 Lyman Oct. 18, 1949 2,838,322 Felts June 10, 1958 2,883,232 Olley Apr. 21, 1959 2,963,300 Purdy Dec. 6, 1960 

